There are many sheet feeders available on the market that all are intended to serve a similar purpose to the sheet feeder of the present invention. Most of the feeders are designed to hold a stack of paper or other materials, hereinafter referred to as sheets, and to feed those sheets one at a time into automated equipment, such as printing, mailing, packaging and other machinery for high speed processing.
The sheet feeder of the present invention includes all of the unique features for which patent protection has been sought in my prior patent application. It also contains several new features for which am seeking patent protection.
Although hundreds of sheet feeder types are available for a wide variety of applications, the improvements in the feeder of the present invention deal primarily with sheet feeding for mail processing equipment, specifically swing arm type envelope inserting machines. Swing arm envelope inserting machines are used by high volume mailers to mechanically insert one or more sheets into envelopes at high speed. These types of inserting machines typically include two or more insert or sheet hoppers and an envelope hopper. These machines normally feed one sheet from each hopper and one envelope from the envelope hopper using vacuum assisted feet, which pull the bottom sheet or envelope from its respective hoppers.
Due to the lack of flexibility in this design, several, but a limited few friction sheet feeders similar to the one of the present invention have been marketed to the mailing industry for many years. Although these feeders perform reasonably well and give the inserting machinery more flexibility, they have several weaknesses that have been improved upon in the present invention.
Specifically, these feeders do not have sufficient sheet guides that extend through the entire machine, allowing sheets to skew as they exit the sheet separation area of the feeders. Additionally, an electronic photo cue that is attached to an arm extending from the end of the feeders must be adjusted to stop each sheet in the proper position for the inserting machine to be able to grab it and pull it away from the feeder. This photo eye must be manually adjusted and is prone to inconsistent set-up and operation. Finally, the prior art feeders do not have any means on the feeder itself to control the height of the sheet that is being delivered to the inserting machine, therefore the operator must install hold down fingers onto the inserting machine to guide the sheets into position. These hold downs are also problematic, as they need to be adjusted for different types of sheets.